(1) Field of the Invention
The present invention relates to an ink cartridge used for an ink jet printer (an ink jet recorder) which discharges an ink from a nozzle of a printing head, and lets it fly and adhere onto a paper or the like.
(2) Description of the Prior Art
An ink cartridge of an ink jet printer is provided with an ink storage chamber (ink tank) for storing the ink, and the ink storage chamber is communicated with an air moving passage such as an air intake or the like. The air moving passage is so constituted that it is closed by a surface tension (capillary force) of the ink, and when the pressure in the ink storage chamber becomes too low with the use (consumption) of the ink, outside air (atmospheric air) is introduced into the ink storage chamber via the air moving passage, to thereby increase the pressure in the ink storage chamber (Japanese Patent Publication No. 2683187, Japanese Patent Publication No. 2684508, Japanese Patent Application Laid-open Hei 2 No. 297498, Japanese Patent Application Laid-open Hei 7 No. 68780, Japanese Patent Application Laid-open Hei 3 No. 169562, Japanese Patent Application Laid-open Hei 8 No. 290585, etc.)
In addition, the ink cartridge is arranged with an ink collector adjacent to the ink storage chamber. The ink collector is constituted such that when the pressure in the ink storage chamber becomes too high due to the temperature increase or the like, the ink collector absorbs a part of the ink from the ink storage chamber and expands the air in the ink storage chamber, to thereby drop the pressure in the ink storage chamber. As the ink collector, there can be mentioned a structure in which an inks is absorbed in micropores in a massive porous body such as a sponge or the like (Japanese Patent Publication No. 2683187, Japanese Patent Publication No. 2684508 and Japanese Patent Application Laid-open Hei 7 No. 68780), and a structure in which an ink is absorbed in ink collector spaces between a plurality of lateral plate-like blade portions arranged in parallel in the vertical direction (top/bottom direction) (Japanese Patent Application Laid-open Hei 2 No. 297498, Japanese Patent Application Laid-open Hei 3 No. 169562, and Japanese Patent Application Laid-open Hei 8 No. 290585).
Moreover, in the case of the ink collector comprising a plurality of blades arranged in parallel in the vertical direction, the structure is such that the ink collector is disposed on the lower side of the ink storage chamber and on the upper side of the printing head, and an intermediary core (ink moving passage) comprising a bundle of fibers is provided penetrating through the blade portions of the ink collector in the vertical direction, thereby an ink is moved by a capillary force of the intermediary core from the ink storage chamber to the printing head side (Japanese Patent Application Laid-open Hei 8 No. 290585), or such that the ink collector is disposed on the lower side of the ink storage chamber and on the lower side of the printing head, and the ink is sucked up from the ink collector by a capillary force of the intermediary core (ink moving passage) (Japanese Patent Application Laid-open Hei 3 No. 169562).
Moreover, in the case of the ink collector comprising a plurality of blade portions arranged in parallel in the vertical direction, the structure is generally such that an ink moving passage (intermediary core, ink introducing groove) for moving the ink between the ink collector space between the blade portions and the ink storage chamber, and an air moving passage (air intake, ventilation passage) for moving the outside air in the ink storage chamber are separately formed (Japanese Patent Application Laid-open Hei 8 No. 290585 and Japanese Patent Application Laid-open Hei 3 No. 169562). Alternatively, the structure is such that an air pipe is connected via an ink inflow port of a container, and the air pipe is communicated with a capillary tank communicating with the air (Japanese Patent Application Laid-open Hei 2 No. 297498).
In the case of the massive porous body such as a sponge or the like, when being cut into a predetermined size, fine cutting wastes (foreign matter) are generated, and fine dust such as the cutting waste or the like may come into the micropores in the massive porous body, and it is difficult to clean and completely remove the fine dust intruded into the interior of the micropores in the massive porous body. Therefore, with an ink cartridge using the ink collector comprising the massive porous body, there is a possibility that fine dust is mixed into the ink from the massive porous body, and the printing head may be clogged with the fine dust.
Moreover, with the ink cartridge using the ink collector comprising the massive porous body, it is difficult to completely use (consume) the ink absorbed by the massive porous body, and only about 50 to 60% of the entire capacity of the ink can be used. Therefore, it is necessary to make the volume of the ink storage chamber larger than the ink volume expected to be used, and thus the ink cartridge becomes large, making it necessary to increase the space for mounting the ink cartridge to the ink jet printer.
Furthermore, with the ink cartridge in which the ink collector comprising a plurality of blade portions arranged in parallel in the vertical direction is disposed on the upper side of the printing head and the ink is moved from the ink storage chamber to the printing head side by means of the intermediary core, since the movement of the ink is performed by a capillary force of the intermediary core, the moving speed of the ink toward the printing head side is slow, and cannot cope with high speed printing. Moreover, with the ink cartridge in which the ink collector comprising a plurality of blade portions arranged in parallel in the longitudinal direction is disposed on the lower side of the printing head, and the ink moving passage and the air moving passage are formed separately, it is difficult to completely suck the ink up from the ink collector to the printing head side. In addition, the technique disclosed in Japanese Patent Application Laid-open Hei 2 No. 297498 is mainly related to a writing instrument, and the construction thereof is different from the other techniques described above as a matter of course.